Geosynthetics is a general term for synthetic materials used in civil engineering. As a civil engineering material, it uses synthetic polymers (such as plastics, chemical fibers, synthetic rubber, etc.) as raw materials to make various types of products and place them inside, on the surface or between various soils. , To play a role in strengthening or protecting the soil. Geosynthetics, different products have different characteristics and can be used in many engineering fields. It has been applied in geotechnical engineering, civil engineering, water conservancy engineering, environmental engineering, traffic engineering, municipal engineering and land reclamation engineering, etc. Geocomposite materials can combine the properties of different materials to better meet the needs of specific projects and can play a variety of functions. For example, composite geomembrane is a geotextile composition made of geomembrane and geotextile according to certain requirements. Among them, the geomembrane is mainly used to prevent seepage, and the geotextile plays a role of reinforcement, drainage and increasing the friction between the geomembrane and the soil surface. Another example is the geocomposite drainage material, which is a drainage material composed of non-woven geotextiles and geonets, geomembranes or geosynthetic core materials of different shapes, used for soft foundation drainage consolidation treatment, roadbed vertical and horizontal drainage, and construction underground drainage Pipes, collection wells, drainage behind the walls of supporting buildings, tunnel drainage, and dam drainage facilities, etc. The plastic drainage board commonly used in roadbed engineering is a kind of geocomposite drainage material.